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Marine Toxins Examples of deadly marine creatures.

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Presentation on theme: "Marine Toxins Examples of deadly marine creatures."— Presentation transcript:

1 Marine Toxins Examples of deadly marine creatures

2 Sea Anemone Toxins are small polypeptides cross-linked by disulfide bridges Toxins are small polypeptides cross-linked by disulfide bridges Classified as Neurotoxins Classified as Neurotoxins Selectively bind to and block sodium and potassium ion channels. 1 Selectively bind to and block sodium and potassium ion channels. 1

3 Ion Channels Help control the excitability of nerve cells by selectively allowing ions across the membrane 1 Help control the excitability of nerve cells by selectively allowing ions across the membrane 1

4 Resting Potential Resting potential of nerve cells is maintained by pumping Na+ to the extracellular side of the membrane and K+ into the cytoplasmic side creating a difference of about Resting potential of nerve cells is maintained by pumping Na+ to the extracellular side of the membrane and K+ into the cytoplasmic side creating a difference of about -70mV 2 -70mV 2

5 Action Potential When a nerve cell becomes excited by a stimulus, Na+ floods in through the open Na+ channel, K+ channels open subsequently allowing K+ to diffuse across to the extracellular side, depolarizing the axon. 3 When a nerve cell becomes excited by a stimulus, Na+ floods in through the open Na+ channel, K+ channels open subsequently allowing K+ to diffuse across to the extracellular side, depolarizing the axon. 3

6 Blocking the Ion Channels, prevents the flow of ions during an action potential, thus inhibiting the conduction of nerve impulses along nerve fibers causing paralysis. 4 Blocking the Ion Channels, prevents the flow of ions during an action potential, thus inhibiting the conduction of nerve impulses along nerve fibers causing paralysis. 4

7 Other Neurotoxin Producing Organisms The Puffer Fish produces tetrodotoxin which is another neurotoxin that blocks ion channels The Puffer Fish produces tetrodotoxin which is another neurotoxin that blocks ion channels One milligram can kill a human One milligram can kill a human Victim dies from respiratory paralysis 4 Victim dies from respiratory paralysis 4

8 The positively charged tetrodotoxin binds to the negatively charged inside of the ion channel 4

9 Zombies Tetrodotoxin is believed to be an ingredient in “zombie powders” produced in Haiti Tetrodotoxin is believed to be an ingredient in “zombie powders” produced in Haiti Victims would be declared dead because they could not move nor speak and buried alive only to be revived later by a “boker” or witch doctor Victims would be declared dead because they could not move nor speak and buried alive only to be revived later by a “boker” or witch doctor They would be beaten and fed pastes with hallucinogenic effects and sold into slavery 5 They would be beaten and fed pastes with hallucinogenic effects and sold into slavery 5

10 Crown of Thorns Starfish Sharp spines can penetrate skin Sharp spines can penetrate skin Spines can also break off and remain embedded Spines can also break off and remain embedded Can cause nausea, vomiting and swelling 1 Can cause nausea, vomiting and swelling 1

11 Produces toxin called asterotoxin, a saponin Produces toxin called asterotoxin, a saponin Saponins are related to steroids 5 Saponins are related to steroids 5 Destroys cell by forming pores in the membrane 7 Destroys cell by forming pores in the membrane 7

12 Stonefish Most venomous fish in the world Most venomous fish in the world Looks like encrusted rock Looks like encrusted rock Has row of thirteen venomous spines on back Has row of thirteen venomous spines on back Terrible pain, temporary paralysis, shock and death can occur 1 Terrible pain, temporary paralysis, shock and death can occur 1

13 Stonefish venom produces intense vasoconstriction, myotoxicity and vascular permeability Stonefish venom produces intense vasoconstriction, myotoxicity and vascular permeability Blocks the conduction of cardiac, smooth and skeletal muscles Blocks the conduction of cardiac, smooth and skeletal muscles Symptoms may last several days or weeks and full recovery may take months 9 Symptoms may last several days or weeks and full recovery may take months 9

14 Stonustoxin Lethal component of Stonefish venom Lethal component of Stonefish venom Induces edema (swelling), vascular permeability and hemo-lytic activity Induces edema (swelling), vascular permeability and hemo-lytic activity Irreversibly interferes with neuromuscular function Irreversibly interferes with neuromuscular function Membrane spanning amphiphilic alpha- helices aggregate to form pores 9 Membrane spanning amphiphilic alpha- helices aggregate to form pores 9

15 Boxes of Death The box jellyfish is the deadliest The box jellyfish is the deadliest Kills more people than crocodiles, sharks and stonefish each year Kills more people than crocodiles, sharks and stonefish each year Up to sixty tentacles that can reach a length of fifteen feet 1 Up to sixty tentacles that can reach a length of fifteen feet 1

16 Each tentacle can have up to five million stinging cells called nematocysts Each tentacle can have up to five million stinging cells called nematocysts Chemicals found on the surface of fish, shellfish and humans trigger the nematocysts to release toxin 1 Chemicals found on the surface of fish, shellfish and humans trigger the nematocysts to release toxin 1

17 The toxins released by the nematocysts have hemolytic, dermonecrotic and myotoxic effects The toxins released by the nematocysts have hemolytic, dermonecrotic and myotoxic effects Current evidence suggest that these toxins may be proteinacious in nature and target specific organs Current evidence suggest that these toxins may be proteinacious in nature and target specific organs These toxins interfere with membrane permeability and may interact with ion channels or receptors 10 These toxins interfere with membrane permeability and may interact with ion channels or receptors 10

18 Acetic acid can prevent the firing of any undischarged nematocysts on the skin Acetic acid can prevent the firing of any undischarged nematocysts on the skin Vinegar is available at most beaches where box jellies are found Vinegar is available at most beaches where box jellies are found Anti-venom can reverse some of the effects of the stings Anti-venom can reverse some of the effects of the stings

19 Irukandji Syndrome Relative of the box jelly Relative of the box jelly Includes several species of jellyfish related to the box jelly Includes several species of jellyfish related to the box jelly Irukandgji video Irukandgji video Irukandgji video Irukandgji video

20 Cone Shells Over 80 species Over 80 species One species, Conus geographus contains enough venom to kill 700 people 1 One species, Conus geographus contains enough venom to kill 700 people 1 Toxins selectively bind to and block sodium ion channels in nerve and muscle cells 12 Toxins selectively bind to and block sodium ion channels in nerve and muscle cells 12 Stings from cone shells can be up to 70% fatal in humans 13 Stings from cone shells can be up to 70% fatal in humans 13

21 Blue Ringed Octopus Octopus (Hapalochlaena) maculosus Very small Very small Venom is found in saliva released from two glands Venom is found in saliva released from two glands The bite itself is usually not noticed. Numbness begins around the mouth and is followed by paralysis The bite itself is usually not noticed. Numbness begins around the mouth and is followed by paralysis Death results from respiratory paralysis 1 Death results from respiratory paralysis 1

22 The blue ringed octopus toxin is called maculotoxin--- it is pharmacologically similar to tetrodotoxin. 14 The blue ringed octopus toxin is called maculotoxin--- it is pharmacologically similar to tetrodotoxin. 14

23 Other Informative Videos Puffer fish Puffer fish Puffer fish Puffer fish Cone shells Cone shells Cone shells Cone shells Banded Sea Krait Snake Banded Sea Krait Snake Banded Sea Krait Snake Banded Sea Krait Snake Stone Fish Stone Fish Stone Fish Stone Fish Stingray Stingray Stingray

24 References faculty.stcc.edu/.../nervssys/unit10/resting.htm faculty.stcc.edu/.../nervssys/unit10/resting.htm faculty.stcc.edu/.../nervssys/unit10/resting.htm Francis, G., Kerem, Z., Makkar, H., Becker, K The biological action of saponins in animal systems: a review. British Journal of Nutrition. 88: Francis, G., Kerem, Z., Makkar, H., Becker, K The biological action of saponins in animal systems: a review. British Journal of Nutrition. 88: &volume=015&issue=04&page= &volume=015&issue=04&page= &volume=015&issue=04&page= &volume=015&issue=04&page=0284 Ghadessy, F., et.al., Stonustoxin is a Novel Lethal Factor from Stonefish (Synanceja horrida) Venom. Journal of Biological Chemistry. 271(41): Ghadessy, F., et.al., Stonustoxin is a Novel Lethal Factor from Stonefish (Synanceja horrida) Venom. Journal of Biological Chemistry. 271(41): Bailey, P., Little, M., Jelinek, G., Wilce, J., Jellyfish envenoming syndromes: unknown toxic mechanisms and unproven therapies. The Medical Journal of Australia. 178(1): Bailey, P., Little, M., Jelinek, G., Wilce, J., Jellyfish envenoming syndromes: unknown toxic mechanisms and unproven therapies. The Medical Journal of Australia. 178(1): Gonoi, T. et.al., The Conus Toxin Geographutoxin II Distinguishes Two Functional Sodium Channel Subtypes in Rat Muscle Cells Developing in vitro. 7(6): Gonoi, T. et.al., The Conus Toxin Geographutoxin II Distinguishes Two Functional Sodium Channel Subtypes in Rat Muscle Cells Developing in vitro. 7(6):

25 Photo References Introduction Slide: 1.http://library.thinkquest.org/05aug/01819/Images/Sea%20Anemone.jpghttp://library.thinkquest.org/05aug/01819/Images/Sea%20Anemone.jpg 2.http://christthetruth.files.wordpress.com/2009/04/puffer-fish.jpghttp://christthetruth.files.wordpress.com/2009/04/puffer-fish.jpg 3.http://images.google.com/imgres?imgurl=http://www.fm/images/news/star fish.jpg&imgrefurl=http://www.fm/news/csp/07_2.htm&usg=__ONo9ERXB NXBFWPfVa__nNaLKn7o=&h=300&w=400&sz=64&hl=en&start=5&tbnid= hzEYsjhs5mxAgM:&tbnh=93&tbnw=124&prev=/images%3Fq%3Dcrown%2 Bof%2Bthorn%2Bstarfish%26gbv%3D2%26ndsp%3D20%26hl%3Den%26 safe%3Dactive%26sa%3DG 4.http://home.datacomm.ch/renebu/stonefish.jpghttp://home.datacomm.ch/renebu/stonefish.jpg 5.http://www.sciencedaily.com/images/2007/04/ jpghttp://www.sciencedaily.com/images/2007/04/ jpg 6.http://www.itsnature.org/wp-content/uploads/2008/02/cone-snail3.jpghttp://www.itsnature.org/wp-content/uploads/2008/02/cone-snail3.jpg 7.http://4.bp.blogspot.com/_0cnXYhlBk1k/SKL3h6Vc0wI/AAAAAAAABuo/G20 Mhy8U6T4/s400/Blue+ringed+octopus.jpghttp://4.bp.blogspot.com/_0cnXYhlBk1k/SKL3h6Vc0wI/AAAAAAAABuo/G20 Mhy8U6T4/s400/Blue+ringed+octopus.jpg

26 Photo References faculty.stcc.edu/.../nervssys/unit10/resting.htm faculty.stcc.edu/.../nervssys/unit10/resting.htm 1.www.unm.edu/.../actionpotential.html 5. rl=http://www.cwru.edu/groups/ANCL/pages/01/01_08.htm&usg=__JsSW6sV71HlF8nsOOlRX-- sw7tA=&h=360&w=480&sz=36&hl=en&start=107&tbnid=08hiTO6aAy9dMM:&tbnh=97&tbnw=129&prev=/image s%3Fq%3Dblocking%2Bion%2Bchannels%26gbv%3D2%26ndsp%3D20%26hl%3Den%26safe%3Dactive%26sa %3DN%26start%3D jellyfish lw.jpg jellyfish lw.jpghttp://photography.nationalgeographic.com/staticfiles/NGS/Shared/StaticFiles/Photography/Images/Content/box- jellyfish lw.jpg


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